aria2: Update init script

This replaces the use of uci_validate_section() with
uci_load_validate(), which removes the need to declare local variables
for every config option.

This also lets procd trigger the validation function directly, and
removes some unnecessary curly brackets.

Signed-off-by: Jeffery To <jeffery.to@gmail.com>

net/aria2/Makefile

@@ -8,7 +8,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=aria2
 PKG_VERSION:=1.34.0
-PKG_RELEASE:=5
+PKG_RELEASE:=6
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.xz
 PKG_SOURCE_URL:=https://github.com/aria2/aria2/releases/download/release-$(PKG_VERSION)/